Internal-combustion engine.



C. S. LINDSAY & D. H. OLIVER.

INTERNAL COMBUSTION ENGINE.

AAPPLICATION FILED SEPT.3,-I9I3. l

Patented May 25, 1915.

3 SHEETS-SHEET I.

3 SHEETS-SHEET 2.

Patented May 25, 1915..

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INTERNAL COIVIBUSTION ENGINE.

LM. "913' Patented May 25,1915.

3 SHEETS SHEET 3- I II WTE@ TEAE@ 'PATENT @FFQE CHARLES SCOTT LINDSAY AND DOGLAS HEJEY OLIVER, F LONDON, ENGLAND.

. INTERNAL-COMBUSTIO ENGINE.

inattesa.

Patented May 25, 1915.

Applcationled September 3, 1913. Serial No. 787,870.

T0 all whom t may concern Be it known that we, CHARLES Sco'rr LINDSAY and DOUGLAS HEDLEY OLIVER, subjects of the King of England, and residing in London, England, respectively, have invented certain new and useful Improvements in lnternal-Combustion Engines, of which the following is a specification.

This invention is for improvements in or relating to" internal combustion engines which operate on the two-stroke-cyole and has for its object to produce an improved form of engine which will give a greater power for its weight and cylinder capacityr than is obtained from the two-cycle engines hitherto made.

The present invention comprises in a twocycle internal-combustion engine the combination with a single-ended explosion-cylinder of an opposed single-ended pump-cylinder with its closed end directed away from the explosion-cylinder, a piston with one end in the explosion-cylinder and the other end in the pump-cylinder, said piston being connected at the point between its ends to the crank-shaft of the engine. In a multi-cylinder engine of this kind each eXplosion-cylinder may be arranged to receive its charge of air from the pump of another cylinder so that a phase displacement other than 180 between the compressor piston and the eX- plosion-piston can be obtained.

According to another feature of the invention there is employed in a two-cycle combustion engine having an air compressor for each combustion cylinder a distributing, and controlling valve operated by the engine to control simultaneously the supply of air to and from the compressor and the supply of air and mixture to the explosion cylinders; the valve may also be adaptedlto serve as the throttle of the engine.

According to another feature of the invention there is used in combination with a single compressor and two air conduits therefrom, to one of which fuel can be admitted, a rotary valve arranged to control both conduits. If desired a single conduit may be divided into two branches at the top and the single valve and its casing be provided with ports and passages for the suction of plain air, delivery of compressed plain air, and delivery of compressed carbureted air respectively. f v

The Carburation of the compressed air in one of the conduits or in one branch of the single conduit is edected by a j et fed from a float feed chamber and according to another feature of the invention a non-return valve is provided in the conduit supplying the jet or in the jet itself to prevent the liquid being forced backward into the float chamber when compressed air is admitted to the conduit.

The single controlling valve above mentioned may according to this invention comprise a cylindrical plug having passages adapted to register respectively with the plain-air branch and carbureted air branch of the compressed air supply-pipe and to put them in communication with the explosioncylinder by one or more ports therein. This valve may be adapted for axial movement so that the ports in the valve and in the casing are displaced from full registration with one another and the rotary valve thereby serves lf desired also the ports in as a throttle. the valve or in the kcasing or in both may be tapered in the manner hereinafter described.

A non-return valve may be situated between the explosion-chamber and the rotary valve to protect the latter from exposure to the ignited gases in the explosion-chamber.

1n the accompanying drawings-Figure 1 is an elevation partly in section, showing a three-cylinder engine constructed in accordance withthis invention; Fig. 2 is a similar view of a modified construction; Fig. is a side view of the rotary valve; Figs. 4-7 are diagrammatic views of the rotary valve in different positions. Fig.A 8 is a section through the inlet port to the cylinder showing the non-return valve above mentioned:

Like reference characters indicate like parts throughout the drawings.

Referring to Fig. 1, the explosion-cylinders A are mounted on a suitable frame wit their open end downward and a compressor cylinder B is mounted in the same axial line beneath each explosion-cylinder A, with its open end pointing upward toward the exp'losion-cylinder. Since the three sections o the engine are alike the description will now be confined to one of them. The pistons A1, B1 of the explosion and compression cylinders respectively are directly coupled together by a member C which 1s provided with a lateral extension C1 about the middle projection C1, is of sufficient length to accommodate the connecting ,rod outside the air compressor cylinder and is of the requisite strength to transmit the power adeveloped in the explosion-cylinder to the crank-shaft. The compressor-cylinder B, may be of the same diameter as the Working cylinder although it is preferred to make it somewhat 'trated in Fig. l to which the larger in order that there may be a surplus of air available for scavenging the explosion-cylinder supplied by the pump. If desired each compression cylinder may bearranged situated directly above it but it is preferred 'to connect it to one of the other eXplosioncylinders so that a phase displacement is obtained in the motion `of the compressor piston and explosion piston.

In the construction illustrated in Fig. 2, the 'explosion-cylinders E1, E2 are arranged in pairs with a common combustion chamber E. Each cylinder, however, has a corresponding compressor-cylinder F1, F2 arranged in the same axial line and beneath them. The four pistons G1, 3 H1, H2 are all coupled together by an H-shaped member K on the transverse portion K1 of which is mounted the connecting rod L to couple the pistons to the crank-shaft. It will be appreciated that in this construction a balanced thrust is obtained on the member K1, and the Whole construction of each section of the engine is symmetrical. In other respects this engine is similar to that illusfollowing description refers.

he compressed air is delivered from the compressor cylinder B, by the coundit B2 to a valve chest M mounted on the side of each explosion-cylinder (Fig. per end.

Referring to Fig. 3, the conduit B2 vided within the valve-chamber M into two passages B3 and B1 which terminate in ports B3, B6 respectively, in the seating of a rotary valve P. Within the passage B3 is situated a jet N, through which fuel is supplied from a float feed beside the valve-chest. This )et acts in the ordinary Way, z'. e., when air is caused to liow'upward through the passage B3, past the jet, some fuel is caused to flow out and the air is carbureted. A non-return valve N2 is provided in the base of the jet to prevent the liquid being forced back from the jet into the float feed chamberwhen the passage B3 is filled with air under a pressure greater than that of the atmosphere. f

In the upper part ofthe valve-chamber M a cylindrical bore is provided to serve as a seating for the rotary valve P, and it is into this bore that the ports B3, B6 above-mentioned open. The port A2 (see Fig. 8)v 'and a passage A3 provide communication between the combustion chamber A and this to supply the explosion-cylinder 1) near its upis di-v chamber N1, situated bore. If desired a non-return valve A4 may be provided (see Fig. 8) in the passage A3 to protect the rotary valve P against the action of hot gases generated in the cylinder during the explosion stroke.

he valve P as illustra-ted in Fig. 3 is provided with a circumferential groove P1 and With' internal passages P2 P3 providing communication between ports' P4 P5 and P3. The function of this valve, is, as mentioned above, to, control simultaneously, the supply of air to and from the compressor and the supply of air and mixture to the explosion cylinders. The rotary valve P is made adjustable in its casing so that the ports in the valve can be made to register more or less with the ports in the valve chamber; this longitudinal movement may be given to it by means of a device P20 coupled to the end of the valve spindle. -This valve P may thus be made to serve as a throttle valve -for the engine. The valve P is coupled to the crank shaft by a chain D20 (Fig. l) so that the valve rotates synchronously with the crank shaft.

It will be understood that skew or other gearing may be drive. The operation of this engine is as follows Considering the explosion piston A1 at the top of its stroke, ignition occurs and used in place of the chain ton approaches the bottom of its stroke it uncovers the exhaust port and aconsiderable portion of the exhaust gas escapes. The rotary valve has then moved around to such a position that the port P1 is open to the passage B1 by which plain compressed air is delivered from the compressor to the port B6 in the valve face. This air passes thence by the port P1 in the valve and passage P2 to the port P5 which is approaching and is partly open to the port A2 communicating withthe cylinder so that a charge of scavenging air is admitted, to assist in clearing out the exhaust gases. When the piston reaches thebottom of its commences to register with the port B5 of the passage B3 and communication is provided by the passage P3 through the port P3 which still registers with the cylinder port A2. As the piston A1 moves upward the port P5 moves out of register with the port A2 and so closes the cylinder completely. The piston continues to move upward and compresses the charge until it reaches the top of its stroke when ignition takes place in the usual way and the cycle of operations is repeated. The cycle is the same in each of the cylinders, and the respective cranks areset at 120 so that a uniform torque and a satisfactorily balanced engine are obtained. The rotary valve P is also used toY control the airl inlet to the com'- pressor as hereinbefore mentioned. vA port incassa ports P7 and B6 so that air can be drawn into the compressor on its suction stroke. The delivery of air from the compressor is controlled by the ports P1 P6 in the valve in the manner above'described.

It will be understood that the arrangement'and positioning of the ports and passages relating to this valve P may be varied within considerable limits. As shown in Figs. 4 7 the valve is so arranged that each cylinder is supplied from a compressor whose crank is 120 behind it in the direction of rotation ofthe main shaft, the direc\ tion of rotation of the valve being indicated by the arrow R, For convenience it 1s assumed that the crank-shaft revolvesin the same direction and the positions of the cranks of a working piston and its corresponding compressor piston are indicated on the valve at S1 and S2. In considering these figures it will be remembered that the explosion cylinder is situated above the crankshaft and the compressor cylinder below the crank-shaft.

In Fig. 4 the working piston has moved downward a short distance on its explosion stroke. 4'Ihe compressor piston as indicated by its crank S2 is about half-way up on its suction stroke and it has commenced to suck in air from the passage P7 through the groove P1 to the port B6.

Fig. 5V illustrates the position somewhat later on the power stroke of the explosion piston. An exhaust port in the cylinder has just been opened by the piston uncovering it and the major portion of the exhaust gas has been allowed to escape. 'Ihe scavenging charge is about to be admitted from the compressor by the passage B'1 port B5 into the valve by the port I"1 and thence by the passage P2 to the port P5 which is coming into register with the cylinder port A2. The compressor piston has completed its upward or suction stroke at which point the air inlet by the groove P1 was cut 0E, and the piston has moved slightly downward on its compression stroke.

Fig. 6 shows the position of the valve when the explosion piston has reached the bottom of its stroke. The supply of scavenging air has been cut-ofi", and the explosive mixture is about to be forced into the cylinder by air being delivered from the compressor through the passage B3 where it is carbureted and when it passes by the ports B5 P6 into` the passage I"3 in the valve through which it passes to the ports P5 and A2 and the explosion cylinder. This other end in said pump cylinder, a

path of communication is closed when the working piston has moved up a short distance on its-compression stroke. The working cylinder is then completely closed and compression commences, continuing until the piston reaches the top of its stroke when ignition takes place and the cycle is repeated.

F ig. 7 shows the position of the valve when the working piston is half-way up on its compression stroke. It will be seen that all the ports are closed for both the working cylinder and the compressor in each of which compression is taking place.

'Ihe above description of a construction of engine according to the present invention has been given by Way of example and it will be understood that modifications may be made in the details of the engine itself and in the arrangement of the valve without departing from the spirit or scope of the invention, as set forth in the appended claims.

What we claim as our invention and desire to secure by Letters Patent is 1. In a two-cycle internal combustion engine the combination of a plurality of explosion cylinders, an equal number of openended pump-cylinders, disposed one opposite each of said explosion cylinders with its closed end directed away therefrom, a piston common to each explosion cylinder and its corresponding pump-cylinder, a conduit connecting each pump-cylinder with an explosion cylinder, and a single distributing and controlling valve controlling the supl of air to and from said pump cylinders and the supply of scavenging air and mixture to said explosion cylinders substantially as set forth.

2. In a two-cycle internal combustion engine the combination of an open-ended explosion cylinder, an opposed open-ended pump-cylinder having its closed end directed away from said explosion cylinder, a piston having one end in said explosion cylinder and the other end in said pump cylinder, a crank-shaft, means operatively connecting said crank-shaft to said piston at a point between its ends, a bifurcated conduit connecting said pump cylinder to said explosion cylinder, a fuel-supply device in one branch of said conduit, and a single distributing and controlling valve controlling the supply of air to and from said pump cylinder and the supply of scavenging air van explosive mixture to said explosive cylinder, substantially as set forth.`

3. In a two-cycle internal combustion engine the combination of, a plurality of singie-ended explosion cylinders, an open-ended pump-cylinder disposed opposite each explosion cylinder and having its closed end directed-away therefrom, a piston having one end in said explosion cylinder and tlliie cran di. alecm,

shaft, means operatively connecting saidfuel supply device in one branch of said conduit, a single distributing and controlling valve controlling the supply of air to and from said pump cylinder and the supply of scavenging air and explosive mixture to said explosive cylinder, a cylinder port, and a non-return valve situated in the fuel supply device substantially as set forth.

Y In a two-cycle internal combustion engine the combination of, a plurality of eX- plosion cylinders, an equal number of openended pump-cylinders disposed one opposite each of said explosion cylinders, with its closed end directed away therefrom, a piston common to each explosion cylinder and its corresponding pump-cylinder, a bifurcated conduit connecting each pump cylinder with an explosion cylinder and a single distributing and controlling valve, controlling ports allocated one to each compressor and communicating with atmosphere, further ports lone of which communicates with each ofthe working cylinders and pairs of ports communicating with the branches of each of the said bifurcated conduits substantially as setv forth.

5. In a two-cycle internal combustion engine the combination, of an open-ended eX- plosion cylinder, an opposed open-ended pumpy cylinder having its closed end directed away from the explosion cylinder, a piston having one end lin said explosion cylinder and the other end in said pump cylinder, a crank-shaft, means operatively connecting said crank-shaft to said piston at a point between its. ends,'a cylindrical valve chest adjacent said cylinder a bifur-A cated conduit connected to the pump cylinder and opening into ports longitudinally 4isposed in said valve-chest, a further port in said valve chest communicating with atmosphere, and situated in the same transverse plane of said valve chest as one of said ports of the bifurcated conduit from the compressor, a port spaced longitudinally from said other ports and communicating with said explosion cylinder, a fuel supply device in the branch to the other of said ports of said bifurcated conduit, a cylindrical valve in said valve chest, an internal passage in said valve havingthree outlets on the circumferential face thereof, said outlets beingspaced longitudinally apart, and

41n the same transverse planes respectively as the cylinder port and the ports for the bifurcated conduit in said valve chest, a parf tial circumferential groove communicating with one of the outlets of said internal passage in said valve and in the ,same trans- Verse plane as the port open to atmosphere in said valve chest, means operatively connecting said rotary valve to, said crank shaft, l

controlling means operating to move said valve longitudinally, substantially as set forth.

l In testimony whereof we have signed our names to this specification in the presence of two subscribing witnesses.

CHARLEs sooTT LINDSAY. DOUGLAS HEDLEY OLIVER.

Witnesses:

O.' J. WORTH, W. E. ROGERS. 

